These are several core values that are prominent in the writings of both Thoreau and Emerson:

1. A strong belief in individuality and being self-reliant in all that one does -- including growing one's own food and building one's own house as Thoreau does in Walden.
2. Though they were intensely individual, they also believed in the concept of the Over-Soul. To put it simply, the Over-Soul is God and they believed there was a piece of the Over-Soul in every human being, uniting us all. Emerson wrote an essay on this concept entitled "The Over-Soul."
3. The idea that truth comes from within rather than through overly empirical explanations and the writings of those in the past. Basically, people who have not studied the classics and philosophy in general are able to generate new insights. 
4. Humans naturally have a strong connection with nature and the natural world. As society becomes more and more complex, humans become further disconnected from nature and more discontent in their lives. 

The Transcendentalists believed in a few main ideas.  Perhaps the two most important are:

• The idea that you should believe in yourself and be guided by your own conscience.  The Transcendentalists believed that blindly abiding by society's rules was the best way to destroy one's humanity.  They believed instead that each person should decide what is right for him/herself.
• The idea that humans and nature are related -- that people are connected to the universe as a whole, to a reality that transcends their own bodies.  They believed that people should seek to get closer to nature as a way of getting closer to themselves and to the Divine.