Cannot instantiate a firefox web driver

I am tryng to learn Selenium and am instantiating a FirefoxDriver, but I get this error:

org.openqa.selenium.remote.UnreachableBrowserException: Could not start a new session. Possible causes are invalid address of the remote server or browser start-up failure.
Build info: version: '2.53.0', revision: '35ae25b1534ae328c771e0856c93e187490ca824', time: '2016-03-15 10:43:46'
System info: host: 'alex-ubuntu', ip: '127.0.1.1', os.name: 'Linux', os.arch: 'amd64', os.version: '3.16.0-73-generic', java.version: '1.8.0_91'
Driver info: driver.version: FirefoxDriver

    at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:665)
    at org.openqa.selenium.remote.RemoteWebDriver.startSession(RemoteWebDriver.java:249)
    ........................
Caused by: java.net.SocketException: Connection reset
    at java.net.SocketInputStream.read(SocketInputStream.java:209)

I am using it with

Firefox Version 47.0, first offered to Release channel users on June 7, 2016

on my Ubuntu Desktop.