© Michael Lacewing Kant on conceptual schemes Michael Lacewing osophy.co.uk

Synthetic a priori knowledge A priori: knowledge that does not require (sense) experience to be known to be true (v. a posteriori) It is not a claim that no experience was necessary to arrive at the claim, but that none is needed to prove it. Knowledge of analytic propositions is a priori. –Analytic propositions can be known to be true or false just in virtue of understanding the meanings of the terms used.

Kant on synthetic a priori knowledge Kant argues we can also have a priori knowledge of some synthetic propositions, i.e. we can have a priori knowledge of how things stand outside the mind. How can we know about the world without depending on sense experience? ‘Sense experience’ isn’t just ‘given’ – we apply a pre-existing conceptual scheme which makes such experience possible.

Conceptual schemes Is sense experience where it all starts? Or does something have to exist before sense experience to make it ‘intelligible’? –Is it a jumble before we apply concepts? Origins of concepts: language (other people) v. structure of the mind (‘reason’) –Language: different languages have different concepts, so lead to different ways of understanding sense experience –Structure of the mind: this is common to everyone, so there is only one (basic) way of making sense of experience

Experience What would it be like to have sensory experience but with no ability to think about it? It would not be experience of anything - the idea of an object is the idea of something that is unified, existing in space and time A confused buzz does not deserve the name ‘experience’ What makes intelligible experience, of objects, possible?

Categories Kant’s answer: certain basic concepts, under which sensory input falls, provide experience; Kant calls these concepts ‘categories’ This conceptual scheme is necessary for any intelligible experience at all, i.e. necessary for experience of objects How does Kant show this?

Causality To experience a (physical) world of objects, we must be able to distinguish the temporal order of our experiences from the temporal order of events. Compare two easily made judgments: –Look around the room - your perceptual experience changes, but the room itself has not changed –Imagine watching a ship sail downstream - your perceptual experience changes, and you say that the scene itself has changed (the ship has moved)

Causality How can we make this judgment? The room: we could have had the perceptions in a different order, without the room being different The ship: we could not have had the perceptions in a different order, unless the ship was moving in a different way With the ship, the order of perceptual experience is fixed by the order of events; the order must occur as it does.

Causality This is the idea of a ‘necessary temporal order’, which is captured by the concept CAUSALITY. Effects must follow causes - where one event does not repeatedly follow another, there is no causal link between the events. CAUSALITY is the concept that events happen in a necessary order.

Causality Without this concept, I cannot distinguish between the order of my perceptions (my perceptions changing) and the order of events (objects changing). But this distinction is needed to experience objects at all. So CAUSALITY is necessary for experience.

Conceptual scheme Kant provides other argues for necessity, unity, substance… They are each aspects of ‘the pure thought of an object’ They are not derived from experience, but logically precede experience - hence they are a priori and innate, part of the structure of the mind.

Conceptual scheme We do not apply these concepts to experience - there is no experience without these concepts. At best, there is a ‘confused buzz’ - but do you experience a confused buzz?? Does it even truly occur, at some moment before applying the concepts? All conceptual schemes must include the categories - this is not given by empirical argument, but a priori argument.

Synthetic a priori knowledge ‘The physical world is governed by causality’, or perhaps ‘All physical events have a cause’ – I can know a priori that these synthetic propositions are true. Synthetic a priori knowledge is also possible because of the structure of our senses, e.g. ‘Nothing can be simultaneously red and green all over’ (about the nature of space)

Mind and world What is the world like independent of these concepts? We cannot say, we cannot even imagine. All thought about the world presupposes these concepts. This casts no doubt on the physical world as we experience it - this we can know contains physical objects etc. - anything that takes the form of an ‘object’ is something to which our concepts have already been applied. There is nothing we could know here, but don’t. What would it be to know anything without using concepts? What is experience that is not experience of objects?