Laravel 5.2 RefectionException

A newbie question ...

To open the first page (index) I have the following in a GamesController:

 public function index()
{
    //show a listing of games
    $games = Game::all();
    return view('index',['games'=> $games]);
}

which works fine. I have at the top of the controller

namespace App\Http\Controllers;
use Illuminate\Http\Request;
use App\Game;

The model is simply

namespace App;

use Illuminate\Database\Eloquent\Model;

class Game extends Model
{
    //
}

In my index page I have a simple list from the db with an edit button which has the code:

<a href="" class="btn btn-default">Edit</a>

In my controller have the following:

public function edit(Request $request)
        {
            $games = Game::find($request->id);
            return view('edit',['games'=>$games]);
        }

but when I press the edit button I get