Ok, so which word would you use?

There´s the list for "reason" from the dictionary:

sebep, neden, illet; delil, tanýt; akýl, fikir, idrak, anlayýþ, aklýselim; mantýk; hak, insaf, adalet

Well, I can say I have certainly sparkled a good discussion here guys! Anyway, ´to employ reason´ really means ´to think´ or ´to use one´s mind´. Hope this helps and thanks for all your efforts. I really do appreciate it!!

ok, and what does "as" mean before "when" in your sentence?

´As´ meaning ´because´ = because when I use my mind (when I think about things), they don´t make sense to me. Is this better?