experienced facts, then it will be a false conception. When we, for instance, use words
like ‘God,”eternity,’ or ‘substance,’ reason is being misused, because nobody has
experienced God, eternity, or what philosophers have called substance. So therefore
many learned dissertations could be written which in actual fact contain no really new
conceptions. An ingeniously contrived philosophical system such as this may seem
impressive, but it is pure fantasy. Seventeenth- and eighteenth-century philosophers
had inherited a number of such learned dissertations. Now they had to be examined
under a microscope. They had to be purified of all hollow notions. We might compare
it with panning for gold. Most of what you fish up is sand and clay, but in between
you see the glint of a particle of gold.”
“And that particle of gold is real experience?”
“Or at least thoughts that can be related to experience. It became a matter of
great importance to the British empiricists to scrutinize all human conceptions to see
whether there was any basis for them in actual experience. But let us take one
philosopher at a time.”
“Okay, shoot!”
“The first was the Englishman John Locke, who lived from 1632 to 1704. His
main work was the Essay Concerning Human Understanding, published in 1690. In it
he tried to clarify two questions. First, where we get our ideas from, and secondly,
whether we can rely on what our senses tell us.”
“That was some project!”
“We’ll take these questions one at a time. Locke’s claim is that all our thoughts
and ideas issue from that which we have taken in through the senses. Before we
perceive anything, the mind is a ‘tabula rasa’—or an empty slate.”
“You can skip the Latin.”
“Before we sense anything, then, the mind is as bare and empty as a blackboard
before the teacher arrives in the classroom. Locke also compared the mind to an un-
furnished room. But then we begin to sense things. We see the world around us, we
smell, taste, feel, and hear. And nobody does this more intensely than infants. In this
way what Locke called simple ideas of sense arise. But the mind does not just
passively receive information from outside it. Some activity happens in the mind as
well. The single sense ideas are worked on by thinking, reasoning, believing, and
doubting, thus giving rise to what he calls reflection. So he distinguished between
‘sensation’ and ‘reflection.’ The mind is not merely a passive receiver. It classifies
and processes all sensations as they come streaming in. And this is just where one
must be on guard.”
“On guard?”
“Locke emphasized that the only things we can perceive are simple sensations.
When I eat an apple, for example, I do not sense the whole apple in one single
sensation. In actual fact I receive a whole series of simple sensations—such as that
something is green, smells fresh, and tastes juicy and sharp. Only after I have eaten an
apple many times do I think: Now I am eating an ‘apple.’ As Locke would say, we
have formed a complex idea of an ‘apple.’ When we were infants, tasting an apple for
the first time, we had no such complex idea. But we saw something green, we tasted
something fresh and juicy, yummy ... It was a bit sour too. Little by little we bundle
many similar sensations together and form concepts like ‘apple,”pear,”orange.’ But in
the final analysis, all the material for our knowledge of the world comes to us through
sensations. Knowledge that cannot be traced back to a simple sensation is therefore
false knowledge and must consequently be rejected.”
“At any rate we can be sure that what we see, hear, smell, and taste are the way