Index said:What you say Maciamo, sounds like and argument which suggests that we have no free will and that our behavior is predetermined genetically and environmentally. Surely though we have some semblance of free will? Despite chemical reactions often affecting behavior and emotions, it is well documented that it is possible to adjust your body temperature by using your mind, which would imply that in this case thought determines chemistry. Is this not a form of free will?
Free will is something that exist from a human point of view. However, from an absolute point of view (the universe), all our actions, thoughts or decisions are the consequence of our interaction with our environment, which we cannot escape from. So looking at the big picture (the universe), everything is like a chain-reaction, and in that way everything is determined, although we humans cannot predict it as we cannot know all the universe.
It does not explain, for example, the later stages of relationships where people make assesements based on mutual experiences together, resulting in decisions pertaining to whether the relationship/love should continue.
Do you mean when "true biochemical love" with one's partner becomes like "family love" ? It is just that the hormonal effects has worn off, and remain the mutual experiences, which create a sentimental bond (i.e. common memory, and peace-of-mind/comfort acquired from knowing the other person very well).
It does not seem to explain concepts such as self sacrifice either, which can be evolutionarily unwise, such as breaking off a relationship where your partner is unhappy with what you can give them, or forgiving infidelity (where you risk spending your resources and energy on bringing up and caring for progeny that is unrelated to you genetically).
That is not evolutionary unwise. Humans are social beings. Not all members of the society have to reproduce. Nature usually select only the fittest, whatever the species. But individual survival is also important, regardless of reproduction. Humans are intelligent and emotional beings. They need to socialise and have someone to share their experiences, thoughts or emotions with. That is why some people decide that it is more advantageous for them to stay in a relationship with no love, or no trust regarding faithfulness, than to be alone, and eventually get depressed and die quicker.
As for "up and caring for progeny that is unrelated to you genetically", it is because we are social beings and what matters is the survival of the species (the group), not one's individual genes (which could be partly passed through a sibling or distant relative anyway). We only share 50% of our genes with our offspring, and there is no guarantee (and probably no necessity) to give 100% of them even having 20 children (they could all lack some particular genes of either parents).