How Do You Know When You Are In Love? 
Different Types of Love: passive love and active love; love at first sight. Published on April 25, 2013 by Philippa Perry in How to Stay Sane
Excerpt: “There are other factors that add to this falling in love feeling – unromantic things such as a complimentary immune system that we instinctively recognise via our olfactory systems…”
My comment: In our award-winning 2001 Neuroendocrinology Letters review: ‘Human pheromones: integrating neuroendocrinology and ethology,’we wrote:
“The ‘affective primacy hypothesis’ [5] asserts that positive and negative affective reactions can be evoked with minimal stimulus input and virtually no cognitive processing. Olfactory signals seem to induce emotional reactions whether or not a chemical stimulus is consciously perceived. We theorize that the importance of human non-verbal signals is based upon information processing, which occurs in the limbic system, and without any cognitive (cortical) assessment. Affect thus does not require conscious interpretation of signal content. Underlying this fact is that affect dominates social interaction and it is the major currency in social interactions [6].”
If not for the unromantic reality of olfactory/pheromonal input, epigenetic effects on hormones, and affective primacy, more people might recognize their animalistic behaviors. They could then think before playing the fool in ‘love’ in one failed relationship after another.
Commitment merely involves thought and not acting like an animal. Clearly, that’s why some people can commit, and why others cannot.
James V. Kohl detailedl how quantized energy-dependent microRNA biogenesis links the pheromone-controlled physiology of reproduction to biophysically constrained viral latency and healthy longevity. Links from what organisms eat to the enzyme-dependent metabolism of food also link metabolic networks to microRNA-mediated genetic networks in the context of RNA interference. Drug therapies alter RNA interference by altering cell type differentiation in all cells of all individuals of all species. For comparison, during the past 26 years, Kohl has detailed how the chemistry of protein folding is biophysically constrained at every level of biological organization by conserved molecular mechanisms.