There are pros and cons to both. I would suggest showing something on both landing page as well as in the footer/near the footer. By balancing out the contents presented in these two locations, a good level of outreach can be achieved. See my reasoning below.
On landing page
Obviously the first thing your visitors see. If one of your business goals is to inform the visitors of your statement of philosophy, this is the ideal spot. You can get the message across quickly as well as subtly demonstrating how important is the philosophy to you. Consider showing a concise easy to read title with a few lines of blurb. Show this version of the message only once - in the landing page - to prevent bombarding the users with the same statement over and over again. However, you'd still need a subtle reminder of the statement showing up throughout the site. This is where footer comes into play.
In/near the footer
Assuming you have a common footer showing up throughout the site, you can place a short version of the statement in/near the footer. Thus your statement of philosophy receives constant impression. Keeping the repeated impression in mind, you should show a less dramatic version here, the slogan or motto only perhaps. This can even be a hyperlink to a page containing detailed discussion of the topic.