For the Founders (and those aforementioned authors) Freedom and Liberty do not mean giving into ones desire to do and say whatever they want. Liberty, as used by the Founders, carries with it the understanding that Humans are social beings as part of a society. It is our reason which guards us against our instincts to "do what we want" This is what separates us from the "Brutes" or "Libertines" Literature from the mid-late 18th century abounds with this play on words distinguishing the Free from the Libertine (Mozart/daPontes "Don Giovanni" probably the most famous example)
In the past 30 years those who exercise Liberty in this Classical sense are often derided in a pejorative as being "thin skinned" or "Politically Correct."
Fortunately today we have more free access to source materials than generations past. We can easily read the Nicomachean Ethics, Consolation of Philosophy, the works of John Locke, David Hume et al. We can go to the online Library of Congress and even the John Adams library online and freely read not only the books he read, but also (what we historians love!) his handwritten notes in the margins so that we can know what he was thinking.
Library of Congress Exhibit on the Pursuit of Happiness
But I will close with a quote from Henry Home, Lord Kames whose works inspired our own nations founders when drafting the Declaration:
"It is probable, that in the following particular, man differs from the brute creation. Brutes are entirely governed by principles of action, which, in them, obtain the name of instincts. They blindly follow their instincts, and are led by that instinct which is strongest for the time. It is meet and fit they should act after this manner, because it is acting according to the whole of their nature. But for man to suffer himself to be led implicitly by instinct or by his principles of action, without check or control, is not acting according to the whole of his nature. He is endued with a moral sense or conscience, to check and control his principles of action, and to instruct him which of them he may indulge, and which of them he ought to restrain. This account of the brute creation is undoubtedly true in the main: whether so in every particular, is of no importance to the present subject, being suggested by way of contrast only, to illustrate the peculiar nature of man."
Essays on the Principles of Morality and Natural Religion.
The Damnation of Don Giovanni