The meaning of life is not happiness. Happiness is a relativist construction. In fact there is no meaning in life, historically. However, we are thrust into a life of meaning. We are no longer given the option of no meaning. As the first meaning was created, so was no meaning given a meaning. Thus we find ourselves in something inescapable.
In a deterministic world we have to be sensitive to the forces we create. Although we can view wind as something causal, due to the arrangement of its causal parts, it exerts an effect much greater than a atomic aspect of its causal parts. Ideas like wind may be causal in nature, but important in their category or function.
Determinists devalue specific time points. Wind is ultimately impotent as a force if we do not understand it as an essence. If we understand wind merely as a product--as the end point of causality--then wind means nothing. By limiting wind to its function and structure we can assess wind to be its own cause. This wind is not an illusion; it is a fact. Similarly, we can understand the forces of our mind this way. We need to limit the various functions and structure of our mind and to view them as causes of themselves--causa sui.
As an observer, to obtain knowledge we need to understand things as causa sui--even if this is an illusion. Things lose meaning when they are no longer causa sui.
With the advent of evolution we stopped seeing objects as causa sui. Instead we are the product of evolution, a mode of causa sui--a function. Perhaps instead of viewing things as products of functions we need to view things as forces. Things can be the cause of themselves by their function and structure. In other words rather than focusing on how something is, we need to focus on what something is.
In this sense, ideas become causa sui. Ideas are by their nature function and structure. Once ideas are conceived they become a force and operate according to their immanent function and structure.
The world of ideas is strange in that it would seem to be non physical in substance. This means that the forces of ideas do not interact in the same way the physical plain is forced to interact. Of course a purely deterministic view would say that ideas are not operating on any kind of plain but are merely presented as according physical determinants in the brain. In this case, though, how do our corresponding representations interact? How are they forced to interact? The brain is forced to make a coherence. The brain is immanently creative.
The eyes and ears inherently limit and categorise. The brain gives these limits value. We create value by our bodily responses corresponding to categories of limits. So we see a berry (the limit of the eyes) we eat the berry and understand the berry (the bodily response). Life then is a series of limiting and categorising and then experiencing. The drivers of learning then are curiosity and memory. Curiosity drives us to try new things. Memory helps us remember those things we have interacted with.