How do we know the science is true? Of course we can observe, but science tells us that we don't directly experience objects .. and just as we could be deceived by a wicked scientist putting electrodes in our brains, we could be deceived, in the same way, into thinking that science was 'real.'Therefore, isn't it true that if we accept this scientific account then we cannot be certain that anything exists out there because we can never directly perceive it. Strangely, if this scientific theory is true we cannot prove it, because we can never perceive anything directly, so we do not know how and from where the experience came into our minds. Even our knowledge of eyes, nerves, bits of brain, is not direct but via electrical and chemical events in our brain!
In the olden days, we thought that there were objects, material things, such as bricks, trees, mountains and goats, which were themselves real and constant in a way independent of our looking and otherwise perceiving them. These were things that had primary qualities which did not change and other qualities, sometimes called secondary qualities, which were our reaction to the primary object, and which did change depending on. These secondary qualities were colour, shape, etc. No thinker suggested that the actual object had these qualities. They were qualities we gave to objects.
For example, a rose might look red to us, but if no one was looking at it, we couldn't really say it was red. We might have said it had the power to elicit the colour red in our minds, but this primary quality of being able to elicit the red sensation was not 'red.' The colour was our reaction to the object. So we assume there was something out there, say next door's cat, which was a real object. However our experience of it, blackness, meowing, shape, etc, were largely our reaction to the real object and not the real object itself.
Have you ever been in a shop to buy something, say curtains, where the colour is very important? Have you heard these stories of people getting home only to find the colour looked different? The curtains were the same curtains in the shop. Their primary qualities hadn't changed, but our experience of them, the secondary qualities, changed when we viewed them under different lighting conditions. Because the length and weight, for example, remain the same, we may be tempted to think these are the primary qualities, and colour is just subjective.
Science rushed off to discover these primary qualities and developed concepts like mass which were supposed to describe the real object. However, pretty soon, we realised that the so called primary qualities were just as much secondary as colour and the rest! Although we can specify conditions and measuring instruments which largely give us consistent results, it is a human being who is perceiving the measuring instruments and their reaction on him or her. We cannot know the real object apart from our perception of it. A question like, 'What does something look like when no one is looking at it?' is clearly nonsense, and unanswerable. (trans4mind.com)