Key-term index

Knowledge or justification that depends on sensory experience or observation.

Knowledge or justification available independently of sensory experience.

The view that human beings seek meaning in a universe that offers no final or guaranteed answer.

The study of intentional action, including how reasons, choices and agency explain what people do.

The branch of philosophy that studies art, beauty, taste and aesthetic experience.

Philosophical traditions shaped by African and diasporic experience, including questions of identity, liberation, culture and knowledge.

A tradition that emphasises clear argument, careful distinctions and the analysis of language or concepts.

The use of analytic methods to examine God, faith, religious language and the rationality of belief.

The study of the moral status of non-human animals and how humans ought to treat them.

The view that complex things are ultimately composed of basic indivisible units.

A method of updating degrees of belief by combining prior probabilities with new evidence.

An approach that explains mental concepts through behaviour, dispositions or public criteria.

The branch of ethics that examines moral questions raised by medicine, healthcare, biology and biotechnology.

Searle's view that consciousness is a real, subjective biological feature produced by the brain.

A tradition examining how race, gender, class and other forms of power shape Black women's lives.

The study of moral responsibilities in commerce, organisations, work and economic decision-making.

Real opportunities to achieve valuable doings and beings rather than resources or satisfaction alone.

An account of justice and welfare focused on people's real opportunities to be and do valuable things.

Descartes's systematic method of withholding assent from any belief that can be doubted in order to find a secure foundation for knowledge.

The tradition arising from Descartes's methods of doubt, rational inquiry and distinction between mind and body.

A theological account of human nature, dignity and purpose in relation to God.

Philosophical inquiry conducted within, or in sustained engagement with, Christian beliefs and concepts.

The view that crime involves rational choice and should meet predictable, proportionate and publicly justified punishment.

The mathematical study of what algorithms can calculate and where computation reaches its limits.

The capacity to represent a scenario coherently in thought; philosophers dispute whether this establishes genuine possibility.

A Chinese ethical and political tradition centred on cultivated character, relationships, ritual and humane government.

Awareness or experience, especially the presence of a subjective point of view.

A tradition that analyses social power and seeks the conditions for emancipation from domination.

An inquiry into the origins, values and effects of inherited moral systems rather than simply accepting them.

The interpretation and evaluation of culture, especially how it expresses values, power and social conflict.

An ancient Greek tradition that rejects convention and luxury in favour of virtue, freedom and plain living.

A Chinese tradition emphasising harmony with the Dao through simplicity, spontaneity and non-forcing action.

Philosophy that challenges colonial structures in knowledge, culture, identity and political life.

Reasoning in which, if the premises are true and the argument is valid, the conclusion must be true.

An approach to ethics centred on duties, rules and what actions are right in themselves.

The argument that order, purpose or apparent design in nature provides evidence of an intelligent designer.

A method of testing and developing ideas through questioning, opposition and reasoned exchange.

An approach that understands ideas, societies or history through developing tensions and contradictions.

Descartes's challenge that waking experience may be indistinguishable from dreaming, undermining certainty based on the senses.

The view that common-sense mental categories such as belief and desire may be radically mistaken and replaced by a mature neuroscience.

The view that knowledge is grounded primarily in sensory experience.

Nozick's view that holdings are just when they arise through just acquisition, transfer and rectification.

A tradition seeking tranquillity through modest pleasure, friendship and freedom from bodily pain and unnecessary fear.

The branch of philosophy that studies knowledge: what it is, how it is justified and where its limits lie.

Giving comparable interests comparable moral weight without discounting them by status or species alone.

The branch of philosophy that studies right action, good character and how life ought to be lived.

Descartes's sceptical scenario in which a powerful deceiver causes systematic error even about apparently obvious truths.

Moral thought centred on freedom, responsibility and creating value without relying on a predetermined human purpose.

The study of the structures of human existence, such as being-in-the-world, possibility, anxiety and mortality.

Philosophy concerned with individual existence, choice, anxiety, faith and the search for meaning.

The tradition that stresses freedom, responsibility and self-creation rather than a fixed human essence.

A reality existing independently of a person's present experience of it.

The study of how gender and power shape knowledge, credibility, inquiry and whose experience is recognised.

Philosophy that examines gendered power and rethinks concepts such as freedom, knowledge, justice and personhood.

The everyday framework that explains behaviour through beliefs, desires, intentions and other familiar mental states.

A possible account showing that divine goodness and power can be logically consistent with moral evil by appealing to significant creaturely freedom.

The pattern of causal relations linking a state to inputs, other internal states and behavioural outputs.

The view that mental states are defined by the causal roles they perform rather than the material composing them.

A method that traces how concepts and practices emerged historically through changing relations of power.

The post-Kantian tradition exploring reality, knowledge and freedom through the activity and structures of reason.

The challenge posed by cases where a belief is justified and true only through luck, suggesting that justified true belief is not sufficient for knowledge.

The claim that preventing harm to others can justify coercive interference, while mere offence or imprudence cannot.

The view that pleasure has a central, or sometimes sole, role in explaining what is good.

The theory and practice of interpretation, especially of texts, history and human experience.

The study of how standards, categories and practices of knowledge change across history.

The study of how concepts develop, travel and change across intellectual and historical contexts.

The view that reality, or our knowledge of it, is fundamentally dependent on mind or ideas.

A stimulus or event that affects a system and helps produce a functional or mental state.

The difficulty of explaining causal contact between a non-physical mind and a physical body.

An immediate rational grasp of a truth or principle without deriving it from observation or a chain of inference.

Rawls's account of fair social principles as those free and equal people would choose without knowing their advantages.

The traditional analysis of knowledge as a belief that is true and supported by adequate justification.

A well-founded grasp of truth rather than a merely sincere belief or lucky guess.

The argument, illustrated by Mary's room, that complete physical knowledge may omit what conscious experience is like.

The study of the nature, authority and purpose of law and its relationship to morality.

A political tradition emphasising individual freedom, rights, equality before the law and limits on power.

A political view giving strong priority to individual liberty, property rights and protection from coercion.

The study of valid reasoning, inference and the structures that distinguish good arguments from bad ones.

The view that everything that exists is fundamentally material or physical.

The inquiry into what can make a human life significant, purposeful or worth living.

A condition of mind such as a belief, desire, intention, sensation or conscious experience.

The branch of philosophy that studies the most fundamental nature of reality and existence.

The capacities and states involved in thought, experience, intention, memory and awareness.

The view that mental states and events are identical with states and events in the brain.

Reality that exists and has features independently of anyone's current thought or perception.

The problem of explaining how mental states and conscious experience relate to physical bodies and brains.

The study of possibility, necessity and the ways reality could or must be.

The view that moral judgements aim at objective truths but are systematically false because no such moral facts exist.

The systematic study of moral value, obligation, character and justified action.

The study of the motives, emotions, reasoning and character involved in moral thought and action.

The view that moral judgement is grounded importantly in human sentiments or emotions.

The possibility that the same mental role could be implemented in different physical materials or systems.

Foot's account of evaluating living things, including human virtues, through the needs and patterns of their life form.

The view that moral principles can be grounded in rational reflection on human nature and its purposes.

Reasoning about God from observation and argument rather than relying only on revealed scripture.

Chalmers's view that consciousness is a fundamental non-physical feature governed alongside the physical world by natural laws.

A later Platonist tradition describing reality as a hierarchy flowing from the One and returning through intellect and contemplation.

The branch of philosophy that studies being and existence: what kinds of things exist and the most fundamental categories of reality.

An approach that clarifies philosophical problems by examining how words function in everyday use.

A behaviour, action or other result produced by a system from its inputs and internal states.

The doctrines and arguments developed by early Christian writers known as the Church Fathers.

The effort to make punishment more proportionate, humane, effective and publicly accountable.

Sensory awareness or representation of objects, events and features of the world.

The study of what makes someone the same person across time and change.

The view that knowledge and value are approached from interpretive perspectives rather than a view from nowhere.

The careful description of the structures of lived experience as they appear from the first-person point of view.

A conceivable physical and behavioural duplicate of a person that lacks conscious experience.

The study of machine intelligence, cognition, responsibility and whether artificial systems could genuinely think.

The study of what attention is and how what we notice shapes knowledge, value and moral response.

The study of education's aims, methods, authority and relationship to freedom and human development.

The study of the nature, rationality and value of emotions in thought and action.

The study of historical explanation, change and whether history has intelligible patterns or meaning.

The study of meaning, reference, communication and the relationship between language and reality.

The study of consciousness, mental states and their relationship to bodies and the physical world.

The study of how sensory experience represents the world and can justify beliefs about it.

The study of how power operates through institutions, knowledge, social practices and relationships.

The rational study of religious concepts, arguments, experiences and practices.

The study of scientific methods, explanation, evidence and what scientific theories tell us about reality.

The view that everything mental is ultimately physical or realised physically.

The Plato-inspired view that intelligible realities such as Forms are more fundamental than changing appearances.

The study of justice, authority, rights, freedom and the proper organisation of political life.

The reasoned improvement of laws and institutions to reduce injustice or better serve public purposes.

The study of the concepts and arguments used to organise collective life and political power.

Ideas about government, authority, freedom and social order understood in their intellectual and historical setting.

The study of moral questions about how many people exist, who exists and how their wellbeing should be compared.

The application of ethical reasoning to concrete choices, professions and public policy.

A tradition that understands meaning, truth and inquiry partly through practical consequences and problem-solving.

The view that actions should maximise the satisfaction of people's informed preferences.

Overlapping chains of memory, intention, belief and character that connect stages of a life.

The felt, first-person qualities of experiences such as pain, colour or taste.

The view that reason can provide substantive knowledge independently of, or prior to, sensory experience.

The view that religious belief can be properly basic rather than inferred from evidence, when formed in an appropriate way.

The view that more than one religious tradition may mediate genuine responses to ultimate reality or salvation.

Political thought centred on freedom from domination, civic participation and the common good.

A political tradition defining freedom as non-domination and emphasising civic self-government and the rule of law.

A medieval method using structured questions and disputation to reconcile reason with authoritative texts.

The view that successful scientific theories describe a mind-independent world, including its unobservable features, approximately truthfully.

Mind-dependent sensory items or appearances proposed as the immediate objects of perception by indirect realists.

The capacity for felt experiences such as pleasure, pain or distress.

The view that political authority or principles are justified through an agreement among free and equal people.

The reasoned evaluation of society that exposes injustice, domination or contradiction.

The study of how testimony, trust, institutions and collective practices shape knowledge.

The study of social relationships, institutions, norms and the conditions of shared life.

An approach centred on questioning, dialogue, the examined life and recognition of one's ignorance.

The view that challenge and suffering can provide conditions for moral and spiritual growth.

The property of a deductive argument that is valid and has all true premises.

Unjustified preference for interests simply because they belong to one's own species.

The view that mind and body are fundamentally distinct kinds of substance.

The view that reality contains only one fundamental substance.

Moral reasoning grounded in beliefs about God, divine law, creation or human purpose.

Kant's view that we know objects as they appear under the conditions of human experience, not things as they are independently of those conditions.

A framework that distinguishes epistemic and metaphysical dimensions of meaning by assigning two kinds of intension.

The view that each type of mental state is identical with a particular type of brain state.

The view that laws and institutions should be judged by their contribution to overall wellbeing.

The ethical theory that actions are right when their consequences maximise overall welfare.

The property of an argument whereby it is impossible for all its premises to be true and its conclusion false.

The view that several genuine values can conflict and cannot always be reduced to a single common measure.

A stable excellence of character, such as justice or courage, that enables someone to feel, judge and act well.

A connected set of reasons intended to support a conclusion.

A claim or idea that a person accepts as true.

Information that counts for or against a claim.

A reason or body of evidence that supports a belief.

A premise is a reason offered in an argument; the conclusion is the claim those reasons support.

The view or method of doubting whether knowledge is possible in some area.

A binding promise or relationship between God and a person or community.

The belief that God chooses a person or people for a particular responsibility.

Being freed from oppression, captivity or unjust control.

Belief that there is only one God.

An early male ancestor or leader of a religious people, such as Abraham.

Sacred writings treated as authoritative by a religious tradition.

Brahman is ultimate reality; Atman is the deepest self, understood by many Hindus as related or identical to Brahman.

Right conduct, duty and the order that sustains life and society.

The moral consequences of actions, which shape future experience and rebirth.

Liberation from samsara and the limitations of ordinary existence.

Hindu worship involving offerings, prayer and devotion to a deity.

The continuing cycle of birth, death and rebirth.

The restoration of the relationship between humanity and God through Jesus' life and death.

The Christian belief that God became human in Jesus.

God's anointed or chosen deliverer; Christians identify Jesus as the Messiah.

An extraordinary event understood as an act or sign of divine power.

A short story used to communicate a moral or religious insight.

Jesus rising from the dead after the crucifixion.

The belief that animals, places, objects or natural forces possess spirit or agency.

An attempt to discover hidden knowledge or the future through signs or ritual practices.

A tradition's connected stories about gods, origins and the meaning of the world.

Something presented to a deity, spirit or sacred power as an act of devotion.

Belief in or worship of more than one god.

A repeated symbolic action performed according to an established pattern.

The relation in which one event or condition brings about another.

Determinism says prior causes fix what happens; libertarianism says some human choices are genuinely free.

The view that reality or a person contains two fundamentally different kinds of thing, often mind and body.

The features that make something the kind of thing it is.

A thing or underlying reality that exists and bears properties.

The condition of existing in, experiencing or being shaped by time.

The view that actions are right because God commands them and wrong because God forbids them.

Human flourishing: living and acting well across a complete life.

Moral evil results from agents' choices; natural evil arises from processes such as disease or earthquakes.

The Christian teaching that humanity inherits a damaged condition caused by the first human disobedience.

The absence or loss of a good that ought to be present.

An attempt to explain why a good and powerful God permits evil and suffering.

A basic class used to organise different kinds of things that exist.

What makes something the same thing over time or across different descriptions.

The mind's capacity to be directed towards or about something.

A necessary truth or being could not be otherwise; a contingent one could have been different or absent.

The whatness of a thing: the nature that makes it the kind of thing it is.

A universal can be shared by many things; a particular is one individual instance.

Kant's unconditional moral command to act only on principles that could apply to everyone.

The view that the moral value of an action depends primarily on its outcomes.

An approach to ethics centred on duties, rules and what actions are right in themselves.

The view that at least some moral claims are objectively true or false.

The view that truth or morality depends on a culture, framework or perspective rather than one universal standard.

An approach to ethics focused on good character and the virtues needed to flourish.

The worldwide community of Muslims joined by faith.

God communicating guidance through chosen messengers or prophets.

Knowledge or guidance disclosed by God, especially to a prophet.

Awareness of God that produces reverence, self-restraint and careful action.

Purity of intention: acting for God rather than praise, status or display.

Islam means willing submission to God and living in accordance with God's guidance.

A recurring model, character or pattern that appears across many stories and cultures.

The spread of ideas, customs or technologies between societies.

Teachings or practices intended for those with special initiation or hidden knowledge.

The proposed common pattern in which a hero leaves, faces trials and returns transformed.

The view that religions share a timeless underlying truth or spiritual source.

The blending of beliefs or practices from different religious or cultural traditions.

The requirement to distinguish legitimate military targets from civilians and protect non-combatants.

Principles for deciding when war may be justified and how it must be fought.

Resisting injustice without using physical violence.

The rejection of war or violence as a way of resolving conflict.

The requirement that force and expected harm must not exceed the good reasonably sought.

The rebuilding of trust and relationships after conflict or wrongdoing.

A person's capacity and right to make informed decisions about their own life.

The duty to promote another person's welfare and act for their good.

The ability to understand, retain, weigh and communicate information needed for a decision.

Voluntary agreement given after receiving and understanding relevant information.

The duty to avoid causing unnecessary harm.

Restricting someone's choice for what is claimed to be their own good.

The right to control what happens to one's own body and to be protected from unwanted interference.

The degree of moral consideration, protection or rights owed to a foetus.

The status of being a person with morally important capacities, relationships or rights.

The capacity to develop a property or status that is not yet actual.

The belief that human life has special or sacred value and should be protected.

The stage at which a foetus may be capable of surviving outside the womb, usually with medical support.

Providing a person with the means or help to end their own life.

The inherent or socially recognised worth of a person that calls for respectful treatment.

The principle that a harmful side effect may be permissible when the intended act is good and the harm is not the means used.

Intentionally ending a person's life to relieve serious suffering, usually in a medical context.

Care that relieves pain and other distress while supporting quality of life in serious illness.

An argument that permitting one step will make a chain of increasingly harmful steps more likely.

Being answerable for decisions, actions and their consequences.

A responsibility to take reasonable steps to avoid foreseeable harm to others.

Distress caused by taking part in, failing to prevent or witnessing actions that violate one's moral convictions.

A failure to take the level of care that a reasonable person or professional should take.

Acting honestly and consistently with the ethical standards of a profession.

The level of care or conduct expected from a competent person in comparable circumstances.

The irreversible loss of all functions of the brain, including the brain stem.

Fairness in how benefits, opportunities, risks and burdens are shared.

The process of deciding how scarce donated organs should be distributed among patients.

An organ-donation system that treats eligible people as donors unless they opt out.

Using treatment or technology not only to restore health but to improve capacities beyond a typical level.

Transplanting living cells, tissues or organs from one species into another.

A conception of identity shaped by a close integration of biological bodies and technology.

A threat that could permanently destroy humanity or severely limit its future potential.

Deliberately altering an organism's genetic material.

The claimed right to alter one's body using medical or technological means.

A family of views questioning fixed ideas of the human and exploring lives transformed beyond current human limits.

Confidence that technological progress can solve major human problems and improve life.

Public, deliberate and usually non-violent lawbreaking intended to challenge injustice.

Holding or promoting ideas far outside accepted democratic or moral limits, especially when they reject others' rights.

The liberty to hold and communicate ideas without unjustified censorship or punishment.

The acceptance that different beliefs and ways of life can coexist within one society.

The process by which someone adopts increasingly extreme ideas, sometimes including support for violence.

The freedom to adopt, change, practise or reject a religion, within justified limits.

Mutual respect and concern among citizens who may disagree deeply but share political life.

An agreement in which different sides each accept less than everything they wanted.

The problem that unlimited tolerance may allow intolerant forces to destroy tolerance itself.

Long-term work to address causes of conflict and develop just, peaceful relationships and institutions.

Hostility, division or discrimination based on membership of a religious or political group.

The enforced or entrenched separation of groups in social life or institutions.

A person or institution's recognised standing as a reliable source of knowledge.

A willingness to rely on another person as a source of information or understanding.

The unwritten values, expectations and habits taught through how education is organised.

Recognising the limits of one's knowledge and remaining open to correction.

A model or framework that shapes which questions, evidence and explanations are accepted.

The theory and practice of teaching and learning.

Certainty is complete confidence that a claim cannot be false; uncertainty is a recognised lack of full assurance.

An approach to education that examines power and enables learners to question and change injustice.

The capacity to form, explore and rearrange ideas or possibilities beyond what is immediately present.

Teaching beliefs in a way that discourages questioning, evidence or genuine alternatives.

A good habit of thinking, such as honesty, curiosity, courage or careful judgement.

Sound judgement about what matters and how to live, informed by knowledge and experience.

An assessment of beauty, artistic merit or aesthetic experience.

A quality or experience that gives aesthetic pleasure, admiration or a sense of fittingness.

The study of how beauty and art relate to God, creation or religious experience.

Artistic representation or imitation of reality.

Objectivism treats aesthetic value as independent of personal preference; subjectivism grounds it in individual response.

An overwhelming aesthetic experience of greatness, power or vastness that can mix awe with fear.

The view that art need not serve moral, political, religious or practical purposes.

The worth an artwork has because of qualities such as form, insight, skill, originality or impact.

Suppressing, restricting or removing expression judged harmful, offensive or threatening.

An account of what an artwork means and how its features support that meaning.

Communication designed to shape attitudes or behaviour, often through selective or manipulative presentation.

A person's cultivated or habitual preferences and judgements about art and beauty.

Unfair treatment of people because of their identity or membership of a group.

Equality gives people the same treatment or resources; equity adjusts support to address different needs and barriers.

An automatic association or judgement that can affect behaviour without conscious intention.

An actual or imagined agreement that explains political authority and citizens' rights and duties.

The government's use or threat of force and penalties to make people comply.

Unfairness produced by the normal operation of social institutions, rules and patterns rather than one isolated act.

The legal execution of a person as punishment for a crime.

Collective action that challenges unjust power, often through organised non-cooperation or protest.

Responsibility shared by members of a group for actions, structures or outcomes produced together.

Involvement in wrongdoing through assistance, support, benefit or culpable silence.

The willingness to act on ethical conviction despite risk, pressure or personal cost.

An approach that seeks to repair harm by involving those affected, encouraging accountability and rebuilding relationships.

The view that community and shared responsibilities are central to identity and social life.

The process of undoing colonial power and its continuing effects on institutions, knowledge and culture.

The study or presentation of a community's shared world-view as philosophy, often debated for treating cultures as too uniform.

Knowledge, history and ideas preserved and transmitted through spoken forms and performance.

The study of critical philosophical reflection expressed by recognised wise thinkers within African communities.

A family of African ethical ideas expressing that personhood and flourishing are formed through humane relationships with others.

The idea that relationships with ancestors continue to shape identity, obligation and community.

The patterns of power and knowledge created by colonialism that continue after formal colonial rule ends.

A wrong done to someone specifically in their capacity as a knower.

Knowledge developed within a community through its history, practices, language and relationship with its environment.

The view that a person's identity is constituted partly through relationships with others.

Universalism seeks principles that apply to everyone; particularism stresses the moral importance of context and specific relationships.

Jesus' death healing the broken relationship between humanity and God.

Preaching the gospel with the intention of converting others to Christianity.

God becoming human in Jesus.

God's infinite goodness and love.

God's unlimited, almighty power.

Jesus rising from the dead and conquering death.

Outward signs of inward divine blessing, including baptism and Eucharist.

The one God as Father, Son and Holy Spirit.

Form, sensation, perception, mental formations and consciousness as the five constituents of a person.

No independent or permanent self.

The impermanent nature of all things.

Suffering or unsatisfactoriness.

The development of loving kindness, usually through meditation.

Dependent origination: phenomena exist through a complex causal web across past, present and future.

Calmness or breathing meditation.

Insight meditation that enables perception of things' true nature.

Voluntary sexual intercourse between a married person and someone other than their spouse.

Living together in a sexual relationship without marriage or civil partnership.

Dedication and obligation to a person or cause.

Methods intended to prevent pregnancy during or after sexual intercourse.

The legal ending of a marriage.

People of all genders having equal rights and opportunities.

Expected actions or duties.

A person's position or function and the behaviour society expects with it.

Ending a pregnancy so it does not result in a birth.

Existence continuing after physical death.

Meeting demands on natural resources without preventing present or future human, animal and plant flourishing.

Killing or allowing the death of a person suffering from serious illness; often called mercy killing.

Development of living creatures from earlier, less complex forms over Earth's history.

The extent to which life is meaningful and pleasurable.

The belief that life is precious or sacred; some religious believers give human life distinctive status.

The non-physical or spiritual aspect of a being, often understood to survive death; the guidance definition links it to God.

Pardoning wrongdoing and giving up resentment or revenge.

Choosing voluntarily and independently rather than being predetermined.

Good is morally right and beneficial; evil is extremely immoral, wicked and wrong.

Fairness, equal provision and equal opportunity.

Principles and standards used to judge actions right or wrong.

A penalty imposed for a crime or wrongdoing.

Deliberate immoral action that breaks a religious or moral law.

Physical, emotional, psychological or spiritual pain or distress caused by injury, illness or loss.

Suppressing or limiting access to material or speech judged offensive, obscene or threatening.

Treating groups or individuals differently because of prejudice.

Believing in and supporting ideas far from what most people consider correct or reasonable.

Basic entitlements held by all people simply because they are human.

Something a person strongly feels or believes.

Judging people inferior or superior in advance and without cause.

Absolute poverty is acute deprivation of basic needs; relative poverty is measured against the standards of the society in which a person lives.

Promoting fairness by challenging injustice, valuing diversity and securing equal provision, opportunity and rights.

Knowledge of how to perform an activity or exercise a skill.

Direct familiarity with a person, place or thing, usually expressed as knowing someone or somewhere.

A case in which a belief is justified and true but true through epistemic luck, challenging JTB as sufficient for knowledge.

A post-Gettier response which strengthens justification so that it guarantees truth or rules out error.

A necessary condition must be present; sufficient conditions, taken together, guarantee that the definition applies.

The proposal that knowledge is JTB plus the condition that the belief is not inferred from any false premise.

Knowledge that a proposition is true; the kind of knowledge analysed by the tripartite view.

The analysis of knowledge as a true belief produced by a process that reliably forms true beliefs.

The analysis of propositional knowledge as justified true belief: belief, truth and justification are jointly sufficient and individually necessary.

An analysis which connects knowledge to true belief produced through intellectual virtues or competent cognitive agency.

The challenge that a subject may have an experience subjectively indistinguishable from perception when no corresponding object is present.

The challenge that illusory experiences seem to present an object as having a property it does not really possess.

Locke argues that our inability to choose many sensory experiences supports an external cause of those experiences.

The view that ordinary objects are collections of mind-dependent ideas rather than mind-independent material substances.

The argument that we cannot conceive of an unconceived object because conceiving it makes it an object of thought.

The view that the immediate objects of perception are mind-independent objects and their properties.

Russell argues that a continuing external world is the simplest and best explanation of the regular sense-data we receive.

The view that we immediately perceive mind-dependent sense-data caused by and representing mind-independent objects.

Variation in how the same object appears under different conditions or to different perceivers.

Locke distinguishes primary qualities possessed by objects from powers to produce ideas of secondary qualities in perceivers.

Because signals take time to reach and be processed by us, perception presents an object as it was rather than exactly as it is now.

Descartes' insight that the occurrence of thinking guarantees the existence of the thinker at least while thinking.

The division of genuine objects of reason into relations of ideas and matters of fact.

For Hume, impressions are forceful original experiences; ideas are fainter copies in thought.

The view that the mind possesses at least some concepts or knowledge independently of sense experience.

Experience supplies particular cases but cannot establish necessity, so our grasp of necessary truths requires an innate rational source.

Locke argues that allegedly innate principles are not consciously accepted by every person, undermining universal assent as evidence of innateness.

Socratic questioning appears to draw geometrical knowledge from an untaught boy, which Plato explains as recollection.

An immediate intellectual grasp of a proposition as true without deriving it from other propositions.

For Locke, experience supplies simple ideas which the mind can combine, compare and abstract into complex ideas.

Locke's image of the mind as a blank slate whose ideas arise from experience rather than innate content.

Berkeley removes the gap between ideas and unknowable material objects by treating ordinary objects themselves as mind-dependent collections of ideas.

The objection that Descartes relies on clear and distinct reasoning to prove God, then relies on God to guarantee clear and distinct reasoning.

Descartes begins with the cogito, then uses clear and distinct ideas and arguments for a non-deceiving God to restore trust in reason and the external world.

The challenge that an experience may feel like waking perception even when it is a dream, undermining certainty about the present external world.

Locke appeals to involuntary and coherent experience, Berkeley removes unknowable matter, and Russell treats the external world as the best hypothesis.

Descartes imagines a powerful deceiver manipulating even apparently self-evident reasoning, creating the most radical wave of doubt.

Descartes notes that the senses sometimes deceive us, giving reason to withhold trust where conditions are poor.

Local scepticism targets knowledge in a domain; global scepticism attempts to challenge knowledge across all domains.

A systematic challenge to whether our beliefs meet the conditions for knowledge, rather than ordinary hesitation about one claim.

Knowledge may require a reliably truth-conducive process, not the subject's ability to rule out every sceptical possibility.